Dialing device for telephones



'May l5, 1928B F HEIZER DIALING DEVICE FOR TELEPHONES Filed May 25. 1927 Patented May 15, 1928.

UNITED STATES FREDERICK HEIZER, OF SIOUX CI'IY, IOWA.

DIALING DEVICE FOR TELEPHONES.

Application filed May 23,

My invention relates to a dialing device for telephones and it is my object to provide a dialing device in which a number may beN called on an automatic phone by pressing 1n succession a plurality of keys, each adapted to rotate the dial y,switch a distance corresponding to a certain digit which that key represents. f

With this and other objects in view,my invention consists in the construction, ar-

rangement and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Fig. 1 is a plan view of the device, the casing being shown in section.

Fig. 2 is a longitudinal, sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is a transverse, sectional view taken on the line 3 3 of Fig. 1.

Fig. 4 is a detail view illustrating the rackreturning mechanism.

My device comprises generally a supporting base 10, to which is secured the frame members 11 and 12 carrying the mechanism inclosed within a casing 13. The ordinary dial switch is diagramatically indicated at 14, mounted on the shaft 15, journalled in the members 11 and 12. Secured to the shaft 15 in spaced relation are a plurality of gear elements 16, 17, 18, 19, 2o, 21, 22, 23, 24,

which are adapted to be successively engaged to rotate the dial switch 14 through successive arcs of rotation for producing the series of interruptingI impulses used in the automatic system for operating' the selectingv mechanism in the central station.

.I have shown nine of the gear elements 16-24 inclusive, so that anumber of nine digits may be called by my device, but it will be understood that for vuse in an average telephone system where only'fve digits are rused, only five gear elements will be necessary.

I provide a shifting pinion 25, secured to a squared shaft 26 and adapted to be carried longtudinally by said'shaft to first engage vthe gear element .16, thence to be rotated by a shaft 26 to rotate the shaft 15, thence to be again shifted to a position between` a gear element 16 and 17 to allow the 1927. Serial N0. 193,564.

and thence to be again moved longitudinally to engage the gear element 17 etc.

Both longitudinal .and rotating movement are coincidentally produced by any one of a series ofkeys 28,29, 30, 31, 32, 33, 34, 35, 36 or 37. The keys may be numbered, as shown in Fig. 1, from 1-9 and 0, consecutively. The keys are mounted on a shaft 38,- being loosely mounted and spaced by Washers 39 and each key is adapted to be connected to the shaft for transmitting rotating movement to it in the direction wherein thekey is depressed by means of a later- `f ally extending lug 39, which engages a pin 40 secured in the shaft. Each key is returned-to its normal position, as shown in Fig.` 2, by a spring 41 and the shaft is returned to its normal position, limited by the contact of the pins 40 against the lugs 39, by a spring 42, which is stretched between the casing 13 and a lever arm 43 secured to the shaft.

Thus when any one of the keys is depressed, it will rotate the shaft without affecting any of the other keys.

Rotation is transmitted from the shaft 38 to the shaft 26 througha train of gears 44, 45, 46 and 47, the latter being shown in Fig.

3 and comprising a pinion slidably mounted Y uponthe shaft 2 6 and held against longi- I tudinal movement by a bracket 48 extending from the frame element 11. Thus as the shaft 26 Lmoves 1ongit1idinally,-the pinion 47 will continue to imxpartv rotating movementl to it and to remain in mesh with the gear 46.

The shaft 26 is slidably mounted in the bracket 48 and-a bearing 49 on the member 12 land is carried longitudinally by a rack 50 in which it is rotatablymounted. The rack 50 has a number of ratchet teeth 51, engaged by a pawl 52, carried on the end of a bell crank lever 53, pivoted at 54 to a. post 55, projecting from the base 10. In or`der to impart the oscillating movement to lthe bell crank lever 53, I provide for each key a cam plunger 56 having the cam surfaces 57 and 58 engaging one edge of a slot 59 in a sliding plate 60. The plate v60rests upon the hase 10 ,between guides 61, the inclined portions 57 and 58 are separated by a vertical portion 62, which varies in length for each key., being short for the num-ber 1 key and `maximum in length for the zero key. Movedialing switch 14 to return to its Aorigin'alament of the plate 60 is transmitted tothe position as by means of the coil spring`27 -bell crank lever 5 3 through the medium of Uli a link 62, a bell crank lever 63, and a link 64. The plate is returned to its normal position, shown in Fig. 2, by a spring 65 and rests against a stop 66 on the base 10. The plungers 56 are pivoted to the keys and are retained against swinging movement by means of' a guide plate 67.

It may now 'be noted that when a key is depressed, the plate 60 will first be moved rearwardlyby the cam face 57, thus moving j the pawl 52 in the direction indicated by the finally moving the driving pinion tothe@ space between the gear element 17 and the arrow 68, a distance sufiicient to engage the moving pinion 25 with the /face gear element 16. During the time that the vertical portion 62 is passing through the slot 59 of the plate 60, the key will transmit rotation to the. shaft 15 through the medium of the train of gears already described and thus will move the switch element 14 a distance corresponding to the particular key and determined by the length of the vertical portionf62 of the plun ver 56. I

When the cam ace 58 engages the plate 60, 'the pinion 25 will be drawn away from engagement with' the gear element 16 to a position between the gear elements 16 and 17. As the key is released, the various springs described will return the operating elements to their original positions with the exception of the rack 50, which will remain in the position in which it wasfieft. The pawl 52 will then beA drawn rearwardly, jumping two of the teeth 51, to position, for again moving the rack forwardly. When'l another key is depressed, the operationwill be repeated, the driving pinion first being moved into engagement with the gear element 17, the depression of the key then serving to rotate the gear element 17 a distance corresponding to ther particular key depressed and next element 18.

Since those keys, which must transmit a greater amount of rotation to the shaft 15, must move through a greater are of rotation around the shaft 38, they are made shorter as shown in Fig. 1, and allowed to move the same distance verticallv as the longer keys.

After all of the digits have been dialed, the

rack must be returned to its original position. For thls purpose l` provide the bell crank lever 69, the long arm of which en gages a projecting lug 70 on the rack 50 and the short arm of which is engaged by the end of a key 71, shown in Fig. 4. The movement of the rack 50 in the direction 68 will raise the key 71 against its own weight and y when the last digit has been dialed, the key 71 is depressed, thereby moving the rack to its original position. The key will then remain depressed, due to its own weight, until the rack has again been'moved during the dialing of a number.

Some changes may be made in the con- 1. In a device of the class described, a dial switch shaft, a plurality of spaced gear elements thereon, a driving pinion, a plurality of pivoted keys, each key corresponding to a digit to be dialed, means operative by. swinging movement of any key for rotating the driving pinion through an` arc commensurate with the digitrepresented by that key, and means operative by any key for first moving the driving pinion into engagement with a gear element and thence moving said driving pinion to a neutral position between the gear element just engaged and the next gear element.

2`. In a device of the class described, a dial switch shaft, a plurality of spaced gear elements thereon, a driving pinion, a plurality of pivoted keys, each ke corresponding to a digit to be dialed and eing limited to an are of movement corresponding in length to said digit, means operative by any key for rotating the driving pinion and means operative by any key for first moving the driving pinion into engagement with a gear element and thence movlng said driving pinion to a neutral position between the gear element just engaged and the next lgear element. t

3. In a device of the class described, a dial switch shaft, a plurality of spaced gear elements thereon, a dr1ving pinion, a plurality of pivoted keys, each key corresponding to a digit to be dialed, means-operative byran key for rotating the driving inion throug an are commensurate with t e digit represented by that key, and means operative by any key for first moving the driving pinion into engagement with a gear element and thence movin said driving pinion to a neutral position etween the gear element just engaged and the nextgear element, a resetting key and means actuated by resetting key for returning the driving pinion to a starting position.

4. In a device of the class described, a dial switch shaft, a plurality of spaced gear elements thereon, a driving pinion shaft slidablymounted for longitudinal movement, a rack supporting said driving pinion shaft, a plurality of keys, each corresponding to a digit to be dialed, means operative by any key for transmitting rotative movement to the driving pinion shaft through an arc .commensurate with the di 't represented by that key and means operative by any key for engaging said rack and thereby movin the driving pinion first into engagement with a lll gear element and thence moving said driving pinion to a neutral position between the gear element just engaged and the next gear element.

5y. In a device of the class described, a dial switch shaft, a plurality of spaced gear elements thereon, a driving pinion shaft slidably mounted for longitudinal movement, a rack supporting said driving pinion shaft, a plurality of keys, each corresponding to a digit to be dialed, means operative by any key for transmitting rotative movement to the driving pinion shaft through an are commensurate with the digit represented by that key and means operative by any key for engaging said rack and thereby moving the driving pinion first into engagement with a gear element and thence moving said driving pinion to a neutral position between the gear element just engaged and the next gear element, a resetting key and means operative by said key engaging one end of the rack to return said rack to a starting position.

Signed this 2l day of May, 1927, in the county of Woodbury and State of Iowa.

, FREDERICK HEIZER. 

